Z80 Computer CPU Card (USB Code Loader)

     The 1730 is a Z80 CPU card with a Z84C0008VEC processor and 64kB of SRAM.  This card uses a USB interface to upload code from a hex file into 64K of flash.  After upload and after power cycling, the SRAM is programmed using DMA. When SRAM programming is complete the bus is released and the Reset# signal is de-asserted to allow the Z80 to operate normally.  The clock is supplied from a 8MHz crystal oscillator or can be provided by the USB controller in a range from DC to 8MHz.

Features

• 3.0 inch wide by 2.5 inch high 4 layer PWB
• 8MHz Z84C0008VEC CMOS Z80 CPU
• 64kB of flash (10k write endurance) for non-volatile program storage that is up-loadable via USB in about 10S
• Flash is transferred to SRAM after upload and after each board power cycle about 50mS
• Fixed 8MHz crystal oscillator or...
• Programmable clock from DC to 8MHz with the ability to halt and single step via serial link
• When the Z80 is halted, any portion of the SRAM can be downloaded over the serial link
• 64kB of SRAM that serves as both the ROM and RAM for the Z80 CPU
• LCD interface mapped to IO port addresses 0b1xxx xxx0 (Control write) and 0b1xxx xxx1 (Data read and write)
• Reset button controls Z80 reset directly
• All Z80 pins are connected to 40 pin dual row socket at bottom of card
• Can be plugged into the Z80 Backplane for expansion and debugging
• Prototyping can be accomplished with the Backplane Proto Card that has pads on a 0.1 inch grid and space for up to four 40 pin DIPs or many more smaller packages
• Signals can be examined visually with the Backplane Signal Watcher or the Piggy Back Backplane Signal Watcher (Allows slot to be used by a plug in card on top of the viewer so the viewer doesn't take up the slot)
• Power supplied by USB Mini-B connection (With or without USB data interface) or from the 5V/2A regulator on the backplane (7 to 35V input)
• Free ZDevStudio assembler available: See Z80 resource page